Yea, some comments on that video performance is just mean. Which is kinda sad because we don't get a collaboration performance often right?
So when there are a chance like that, there are still people that bashing the other performers
It's sad because they can't enjoy the show, but only the people they care about
Exactly! It's really a shame because we don't get these types of performances often because they know that it ends up in so many people from each fandom praising only their faves and bashing the ones that they didn't like. It's kind of sad but this is the group of fandoms we live in. It's not every fan, there are still many supportive of everyone, and even if they didn't like one idol's performance, they'd be respective about it or at least keep those opinions to themselves.
It's those fans who act negatively during these performances that ruin it for the rest of us who want to see more of these... 
